In order to use radio-frequency (RF) devices in advanced RF networks (such as third generation (3G) and Long Term Evolution (LTE) cellular networks), the devices must undergo compliance testing to assure that the devices will function correctly within the network and will not introduce interferences into the network.
Such compliance tests are performed by using dedicated test equipment (such as the Agilent VSA and ESG) which is highly complex and incorporates a lot of high-end RF circuitry.
The dedicated test equipment is based on high quality receiver and transmitter components which receive and transmit RF transmissions across the entire scope of the different cellular standards. Therefore, each transmission configuration requires its own RF chain which is unique for this specific configuration and differs from other configurations by frequency ranges, bandwidths, amplitudes etc.
FIG. 1a of the prior art is a schematic block diagram of a transmitting path 610′ of a prior art test equipment.
The Tx Data 606′ is input to a Tx hardware path block 600′ containing several Tx paths each of which is a full hardware RF transmitter of a specific standard such as a Tx CDMA path 601′, a Tx WCDMA path 602′, a Tx GSM path 603′, a Tx GPRS path 604′, and a Tx WiFi path 605′. The Tx hardware path block 600′ outputs the Tx Data 606′ through the hardware path selected to be tested to a Tx RF front end 607′ which in turn, transmits its output out of the prior art test equipment.
FIG. 1b of the prior art is a schematic block diagram of a receiving path 610″ of a prior art test equipment.
In the receiving path 610″, a Rx RF front end 607″ receives a transmission from outside the prior art test equipment and inputs it to a Rx hardware path block 600″ containing several Rx paths each of which is a full hardware RF receiver of a specific standard such as a Rx CDMA path 601″, a Rx WCDMA path 602″, a Rx GSM path 603″, a Rx GPRS path 604″, and a Rx WiFi path 605″. The Rx hardware path block 600″ outputs a Rx data 606″ for analysis by the prior art test equipment.
Such dedicated test equipment is very accurate but in many case such accuracy may be excessive and lower accuracy (and much less complex) test equipment can be used.
Using a digital processing software to emulate the different RF transmission signals can help to lower the complexity of the test equipment by eliminating the multitude of RF chains in the dedicated test equipment and thereby simplifying the design of the test equipment.
Using Digital signal processing software any additional transmission configuration (i.e modulation, networking etc.) can be added without the need for multiple hardware RF chains and hardware transceivers.
None of the prior art devices comprises all of the above characteristics and functions.
There is therefore a need for a system and method for measurement of parameters of radio-frequency transmission devices by utilizing a digital signal processing techniques, which comprises a combination of all of the above characteristics and functions.